Examples of Planck sources with an obvious counterpart at optical and infrared wavelengths. On each row, the different panels represent an optical g-band image from SDSS DR9 (Ahn et al. 2012), near- and mid-infrared images at 3.4 and 12 μm from the WISE survey (Wright et al. 2010), the Herschel/SPIRE 350 μm image from HeViCS, and a 20 cm radio continuum image from the VLA-FIRST radio survey (Becker et al. 1995). Each panel is 12 × 12 arcmin², and the yellow circle indicates the beam size of the HFI instrument at 857 GHz. The top two rows correspond to sources with individual Virgo Cluster galaxies as counterparts, the bottom two rows correspond to two pairs of Virgo Cluster galaxies.